Vacuum pump

Abstract

A vacuum pump, which is connectable to an external system and configured to evacuate material from the external system, includes a main housing including a motor housing, a pump housing, and a partition wall that separates the motor housing and the pump housing. The pump housing is sealed relative to the motor housing to form a compression chamber that holds a lubrication fluid. The vacuum pump further includes a motor assembly that is positioned within the motor housing and a pump assembly that is positioned within the compression chamber. The pump assembly is driven by the motor assembly and is in fluid communication with the compression chamber. The pump assembly includes a pump chamber, a rotor having vanes that is driven within the pump chamber, and a seal that is in sliding contact with the rotor. The seal is moveable relative to the rotor.

What is claimed is: 
     
         1 . A vacuum pump that is connectable to an external system and configured to evacuate material from the external system, the vacuum pump comprising:
 a main housing including a motor housing, a pump housing, and a partition wall that separates the motor housing and the pump housing, the pump housing is sealed relative to the motor housing to form a compression chamber that holds a lubrication fluid;   a motor assembly that is positioned within the motor housing;   a battery that is coupled to the motor housing and configured to supply electrical current to the motor assembly; and   a pump assembly that is positioned within the compression chamber, the pump assembly is driven by the motor assembly and is in fluid communication with the compression chamber,   wherein the pump assembly includes a pump chamber, a rotor having vanes that is driven within the pump chamber, and a seal that is in sliding contact with the rotor,   wherein the seal is moveable relative to the rotor,   wherein the seal is approximately tangentially engaged with an outer surface of the rotor, and   wherein the seal includes a wall section having a radius equal to a radius of the pump chamber, while the rotor includes a radius that is less than the radius of the pump chamber.   
     
     
         2 . The vacuum pump of  claim 1 , wherein the seal is movable along a direction perpendicular to a drive axis of the motor assembly. 
     
     
         3 . The vacuum pump of  claim 1 , wherein the seal is biased toward the rotor via a spring. 
     
     
         4 . The vacuum pump of  claim 3 , wherein the spring has a stiffness configured to maintain sealing contact while minimizing frictional wear. 
     
     
         5 . The vacuum pump of  claim 1 , wherein the rotor is eccentrically mounted within the pump chamber. 
     
     
         6 . The vacuum pump of  claim 1 , wherein the vanes are biased outward toward an interior surface of the pump chamber via centrifugal forces. 
     
     
         7 . The vacuum pump of  claim 1 , wherein the seal is in continuous engagement with the rotor and the vanes as the rotor rotates. 
     
     
         8 . The vacuum pump of  claim 1 , wherein the pump assembly includes a valve positioned at an outlet of the pump chamber configured to selectively release evacuated material into the compression chamber. 
     
     
         9 . The vacuum pump of  claim 1 , wherein the pump chamber is a first pump chamber and the rotor is a first rotor, wherein the vacuum pump further includes a second pump chamber and a second rotor that is driven within the second pump chamber, wherein the first pump chamber and the second pump chamber are fluidly connected together in series. 
     
     
         10 . The vacuum pump of  claim 9 , wherein the first pump chamber has a first pump inlet and a first pump outlet, and the second pump chamber has a second pump inlet and a second pump outlet, wherein the first pump outlet is in fluid communication with the second pump inlet. 
     
     
         11 . The vacuum pump of  claim 10 , wherein the second pump outlet is in fluid communication with the compression chamber. 
     
     
         12 . The vacuum pump of  claim 1 , further comprising an inlet manifold positioned on the partition wall, wherein the inlet manifold fluidly connects the pump assembly to the external system. 
     
     
         13 . A vacuum pump that is connectable to an external system and configured to evacuate material from the external system, the vacuum pump comprising:
 a main housing including a motor housing, a pump housing, and a partition wall that separates the motor housing and the pump housing, the pump housing is sealed relative to the motor housing to form a compression chamber that holds a lubrication fluid;   a motor assembly that is positioned within the motor housing;   a battery that is coupled to the motor housing and configured to supply electrical current to the motor assembly; and   a pump assembly that is positioned within the compression chamber, the pump assembly is driven by the motor assembly and is in fluid communication with the compression chamber,   wherein the pump assembly includes a pump chamber, a rotor having vanes that is driven within the pump chamber, and a seal that is in sliding contact with the rotor and includes a wall section,   wherein the seal is moveable relative to the rotor, and   wherein the pump chamber includes a first fillet edge that is adjacent the seal and the wall section includes a second fillet edge that is adjacent the first fillet edge, the first and second fillet edges facilitating the vanes of the rotor to slide between the pump chamber and the seal without jamming.   
     
     
         14 . The vacuum pump of  claim 13 , wherein the first and second fillet edges are configured to reduce wear on the vanes and prevent the vanes from catching on a shoulder of the rotor. 
     
     
         15 . The vacuum pump of  claim 13 , wherein the seal is retained within the pump chamber via a spring disposed in a recess formed in the pump housing. 
     
     
         16 . The vacuum pump of  claim 13 , wherein the seal is movable along a direction perpendicular to a drive axis of the motor assembly. 
     
     
         17 . The vacuum pump of  claim 13 , wherein the rotor is eccentrically mounted within the pump chamber. 
     
     
         18 . The vacuum pump of  claim 13 , wherein the vanes are biased outward toward an interior surface of the pump chamber via centrifugal forces. 
     
     
         19 . The vacuum pump of  claim 13 , wherein the pump chamber is a first pump chamber and the rotor is a first rotor, wherein the vacuum pump further includes a second pump chamber and a second rotor that is driven within the second pump chamber, wherein the first pump chamber and the second pump chamber are fluidly connected together in series. 
     
     
         20 . The vacuum pump of  claim 19 , wherein the first pump chamber has a first pump inlet and a first pump outlet, and the second pump chamber has a second pump inlet and a second pump outlet, wherein the first pump outlet is in fluid communication with the second pump inlet.